Point-to-point connection topology for stacked devices

ABSTRACT

The point-to-point interconnection system for stacked devices includes a device, a substrate, operational circuitry, at least three electrical contacts and a conductor. The substrate has opposing first and second surfaces. A first electrical contact is mechanically coupled to the first surface of the device and electrically coupled to the operational circuitry. The second electrical contact is mechanically coupled to the first surface. The third electrical contact is mechanically coupled to the second surface opposite the first electrical contact. The conductor electrically couples the second electrical contact to the third electrical contact.

TECHNICAL FIELD

The embodiments disclosed herein relate to semiconductor devices, and inparticular to point-to-point interconnection systems for stackeddevices.

BACKGROUND

As computer systems evolve, so does the demand for increased memory forsuch systems. To increase memory density, some memory modules stackintegrated circuit (IC) dies one on top of the other. While memorysubsystems commonly use die-stacking, System-in-Package (SIP) systemsmay also include stacked IC processor and controller die. These stackedsystems permit high IC densities, thereby increasing the memory capacityof each module without requiring additional space on the underlyingcircuit board. Die stacking, however, does present a number ofdrawbacks, as described below.

In these stacked systems, the bare silicon die are typically given anovercoat of oxide to protect the die during handling. A redistributionlayer (RDL) of metal may then be deposited on top of this oxide to forman external interconnection system. Holes or contacts are then etched inthe oxide so the RDL metal can connect to the internal metal layers ofthe silicon die. When the silicon die are assembled into a verticalstack, the RDLs allow signals to pass through the stack.

Such RDLs may be appropriate for bussed (multi-drop) connections, whereall of the silicon die in a stack are coupled to the same bus. However,such RDL systems are not well suited to point-to-point connections,where separate connections need to be made to individual die in thestack. This is because point-to-point connections typically requirecomplex and custom RDLs on each die to properly route the signalsthrough the stack. These custom RDLs on each silicon die are complex andcostly to design and manufacture, particularly in the case in which allthe silicon die are the same (e.g., memory die). Accordingly, a systemthat eliminates custom RDLs in a stacked system would be highlydesirable.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the disclosure herein, reference should bemade to the following detailed description taken in conjunction with theaccompanying drawings, in which:

FIG. 1A is a schematic cross-sectional side view of a point-to-pointinterconnection system for stacked devices, according to an embodiment;

FIG. 1B is a schematic plan view of the system shown in FIG. 1A, asviewed along line 1B-1B′ of FIG. 1A;

FIG. 2 is a schematic cross-sectional side view of one of the devicesshown in FIGS. 1A and 1B;

FIG. 3 is a schematic cross-sectional side view of another device thatmay be used in the point-to-point interconnection system shown in FIGS.1A and 1B, according to another embodiment;

FIG. 4A is a schematic cross-sectional side view of yet anotherpoint-to-point interconnection system for stacked devices, as viewedalong line 4A-4A′ of FIG. 4C, according to yet another embodiment;

FIG. 4B is a schematic cross-sectional side view of the point-to-pointinterconnection system of FIG. 4A, as viewed along line 4B-4B′ of FIG.4C; and

FIG. 4C is a schematic plan view of the systems shown in FIGS. 4A and4B.

Like reference numerals refer to the same or similar componentsthroughout the several views of the drawings.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The following description describes various point-to-pointinterconnection systems. Point-to-point interconnect topology may berequired for a number of reasons, such as (i) the die stack may connectto signals that are used by only one of the silicon die (e.g., achip-select signal in the case of a memory die), (ii) point-to-pointinterconnect topology permits higher signaling rates than multi-droptopology, and/or (iii) point-to-point topology has fewer resourcecontention issues than a multi-drop topology (i.e., read-writeturnaround and tri-state enable/disable delays).

In some embodiments, a point-to-point interconnection system includes adevice having opposing first and second surfaces. The device includesoperational circuitry, first, second and third electrical contacts, anda conductor. The first electrical contact is mechanically coupled to thefirst surface and electrically coupled to the operational circuitry. Thesecond electrical contact is mechanically coupled to the first surface,while the third electrical contact is mechanically coupled to the secondsurface opposite, and aligned with, the first electrical contact. Theconductor electrically couples the second electrical contact to thethird electrical contact. The device may be an integrated circuit die oran integrated circuit package containing at least one die.

In other embodiments, a stacked device assembly includes a plurality ofsubstantially identical devices stacked one on top of the other. Eachdevice has a first surface and an opposing second surface, and includesoperational circuitry, a first row of electrical contacts, a second rowof electrical contacts, and a plurality of conductors. The first row ofelectrical contacts is arranged on the first surface such that eachelectrical contact is separated from an adjacent electrical contact by apredetermined distance. A first electrical contact of the first row ofelectrical contacts is electrically coupled to the operationalcircuitry. The second row of electrical contacts is arranged on thesecond surface, where each electrical contact is separated from anadjacent electrical contact by the predetermined distance. The secondrow is offset from the first row along the second surface by thepredetermined distance. Each of the plurality of conductors iselectrically coupled to a respective electrical contact in the first andsecond row.

In yet other embodiments, a stacked device assembly includes first andsecond devices each having a first surface and an opposing secondsurface. Each device includes operational circuitry, a first electricalcontact, a second electrical contact, a third electrical contact, and aconductor. The first electrical contact is mechanically coupled to thefirst surface and electrically coupled to the operational circuitry. Thesecond electrical contact is mechanically coupled to the first surface.The third electrical contact is mechanically coupled to the secondsurface opposite, and aligned with, the first electrical contact. Theconductor electrically couples the second electrical contact to thethird electrical contact. The second device is stacked adjacent thefirst device with the first surface of the second device locatedadjacent the second surface of the first device. The first electricalcontact of the second device is aligned with and is electrically coupledto the third electrical contact of the first device.

FIG. 1A is a schematic cross-sectional side view of a point-to-pointinterconnection system 100 for stacked devices (as viewed along line1A-1A′ of FIG. 1B). As shown, multiple devices 102(1)-102(4) are stackedone on top of the other. The devices may be stacked symmetrically aboveone another, as shown, or they may be offset from one another, i.e.,arranged in a stair-like manner. In some embodiments, each of themultiple devices 102(1)-102(4) are identical. In some embodiments, eachof the multiple devices 102(1)-102(4) may have different operationalcircuitry, but may still have electrical contacts 104 located at theidentical positions, e.g., may have identical RDLs. In use, the stack ofmultiple devices 102(1)-102(4) is mechanically and electrically coupledto a substrate 101, such as a motherboard.

In some embodiments, each of the multiple devices 102(1)-102(4) is anintegrated circuit or die. In other embodiments, each of the multipledevices 102(1)-102(4) is a separate integrated circuit packagecontaining at least one integrated circuit or die. In yet otherembodiments, each device is a module containing one or more dies orpackages. The devices in the stack may also be any combination of theaforesaid devices. For example, each of the multiple devices102(1)-102(4) may be a single die or a package containing multiple die,such as a memory module or a System-in-Package (SIP). As will bedescribed in further detail below, one of the advantages of thepoint-to-point interconnection system 100 is that it facilitatespoint-to-point connections to any of the devices in a stack withoutrequiring a custom RDL for each device, as all of the devices are eitheridentical or the layout of their electrical contacts are identical.

FIG. 2 is a schematic cross-sectional side view of one of the devices102 shown in FIGS. 1A and 1B. The device 102 includes a substrate 110,operational circuitry 112, multiple electrical contacts or connectors104 and multiple conductors 114 and 116. In the embodiments where thedevice is an integrated circuit, the substrate 110 may be a siliconsubstrate. In the embodiment where the device is a package or modulecontaining multiple integrated circuits, the substrate 110 may be aprinted circuit board (PCB), ceramic substrate, or the like. The device102 has opposing first and second sides 106(1) and 106(2), respectively.In some embodiments, the substrate 110 is substantially planar, i.e.,has substantially flat opposing first and second surfaces.

The operational circuitry 112 may be embedded into, or internal to, thesubstrate 110, as shown, or mounted on the substrate 110, as shown inFIGS. 4A and 4B. In the embodiments where the device is an integratedcircuit, the operational circuitry may include one or more transistorsembedded into the die. In the embodiment where the device is a packageor module containing multiple integrated circuits, the operationalcircuitry 112 may be an integrated circuit or die. In some embodiments,multiple discrete operational circuitry components 112 are provided perdevice, as shown in FIG. 1B.

In some embodiments, the multiple electrical contacts 104 include atleast three electrical contacts 104(1), 104(2), and 104(3). In otherembodiments, the device may include as many electrical contacts 104 asis required. Some embodiments include an array 200 of multiple rows202(a)-202(d) of electrical contacts 104, as shown in FIG. 1B. Theelectrical contacts may take on any form such as metallic bumps or padsformed or etched onto the surface or RDL of the device 102. In someembodiments, each electrical contact 104 in a row 202 (FIG. 1B) on eachside of the device is separated from an adjacent electrical contact inthat row by the same predetermined pitch (p) (FIG. 2). Also in someembodiments, each electrical contact on the second surface 106(2) of thedevice is aligned with a respective electrical contact on the firstsurface 106(1) of the device, along an imaginary line 115 perpendicularto the surface of the device or parallel to the stacked direction. Forexample, electrical contact 104(3) is aligned (e.g., collinear) withelectrical contact 104(1) along an imaginary line 115 that isperpendicular to the first and second surfaces 106(1) and 106(2),respectively; and electrical contact 104(1) is separated from electricalcontact 104(2) by a pitch (p). In other words, in some embodiments, theelectrical contact 104(3) is arranged opposite the electrical contact104(1); the electrical contact 104(5) is arranged opposite theelectrical contact 104(2); etc.

In some embodiments of the invention, the first electrical contact104(1), which is mechanically coupled to the first surface 106(1) of thedevice, is electrically coupled to the operational circuitry 112 via anoperational circuitry electrical conductor 116. The second electricalcontact 104(2), which is mechanically coupled to the first surface106(1) of the device, is electrically coupled to the third electricalcontact 104(3), which is mechanically coupled to the second surface106(2) of the device, via a first electrical conductor 114(1). Theelectrical conductors may be any suitable electrical conductors thatelectrically and/or mechanically couple components together, such aswires, redistribution layers, vias, any combination of theaforementioned, or the like.

In other embodiments of the invention, other electrical contacts areelectrically coupled to one another via different electrical conductors.For example, a fourth electrical contact 104(4), which is mechanicallycoupled to the first surface 106(1) of the device, is electricallycoupled to a fifth electrical contact 104(5), which is mechanicallycoupled to the second surface 106(2) of the device, via a secondelectrical conductor 114(2). Similarly, a sixth electrical contact104(4), which is mechanically coupled to the first surface 106(1) of thedevice 102, may be electrically coupled to a seventh electrical contact104(5), which is mechanically coupled to the second surface 106(2) ofthe device, via a second electrical conductor 114(3). It should beappreciated that any number of electrical contacts may be provided.

Referring to FIGS. 1A, 1B and 2, in use, a signal to be routed to theoperational circuitry 112(1) of the first device 102(1) is communicatedto the first electrical contact 104(1) of the first device 102(1); andcommunicated from the first electrical contact 104(1) to the operationalcircuitry 112(1) of the device 102(1) via the operational circuitryconductor 116 of the first device 102(1). However, to route a signal tothe operational circuitry 112(2) of the second device 102(2) in thestack, the signal is communicated to the electrical contact 104(2) ofthe first device 102(1); communicated through the first conductor 114(1)to the third electrical contact 104(3) of the first device 102(1);communicated from the third electrical contact 104(3) of the firstdevice 102(1) to the first electrical contact 104(1) of the seconddevice 102(2); and communicated from the first electrical contact 104(1)of the second device 102(2) to the operational circuitry 112(2) of thesecond device 102(2) via the operational circuitry conductor 116 of thesecond device 102(2). In a similar manner, a signal to be routed to theoperational circuitry 112(3) of the third device 102(3) is communicatedto the fourth electrical contact 104(4) of the first device 102(1) andis routed through the first and second devices to the third device; anda signal to be routed to the operational circuitry 112(4) of the fourthdevice 102(4) is communicated to the sixth electrical contact 104(6) ofthe first device 102(1) and is routed through the first, second andthird devices to the fourth device. Accordingly, the identical (orsubstantially similar) layout of electrical contacts and interconnectingconductors on the devices allows point-to-point connections to be madeto all of the devices in the stack without requiring a customized RDLfor one or more of the devices.

FIG. 3 is a schematic cross-sectional side view of anotherpoint-to-point interconnection system 300 for stacked devices. In thisembodiment, a RDL is created that wraps around at least one edge of thedevice to route signals between corresponding electrical contacts. Asshown, the RDL may include a first RDL 302 on the first surface of thedevice, a second RDL 304 on the second surface of the device, and athird RDL 306 at an edge of the device that couples the first RDL 302 tothe second RDL 304. It should, however, be appreciated thatcorresponding electrical contacts may be electrically coupled by anysuitable means, such as by a different RDL to that described above, byvias through the device, a combination of RDLS and vias, etc. Forexample, the RDL may consist of any metal applied to the top and bottom(or front and back) of the silicon die, or it may alternatively consistof holes (vias) etched from the top surface to the bottom surface (orback surface to the front surface), with metal deposited in the holes.In an alternative embodiment, a flexible tape is used as a RDLsubstitute.

FIG. 4A is a schematic cross-sectional side view of yet anotherpoint-to-point interconnection system 400 for stacked devices. In thisembodiment, three devices 402 are stacked on top of one another. In someembodiments, each of the multiple devices 402 are identical. In otherembodiments, each of the multiple devices 402 have different operationalcircuitry, but still have identically located electrical contacts 408.In use, the stack of multiple devices is mechanically and electricallycoupled to a substrate, such as a motherboard (not shown).

Each device 402 includes a substrate 404, operational circuitry 406,multiple electrical contacts or connectors 408 and multiple conductors410, 412, and 414. In the embodiments where the device 402 is anintegrated circuit, the substrate 404 may include a silicon substrate.In the embodiments where the device is a package or module containingmultiple integrated circuits, the substrate 404 may be a printed circuitboard (PCB) or the like. The device 402 has opposing first and secondsides 418 and 420, respectively. In some embodiments, the substrate 404is substantially planar, i.e., has substantially flat opposing first andsecond sides.

The operational circuitry 406 may be embedded into the substrate 404 ormounted on the substrate 404, as shown. In the embodiments where thedevice is an integrated circuit, the operational circuitry may includeone or more transistors embedded into the die. In the embodiment wherethe device is a package or module containing multiple integratedcircuits, the operational circuitry may be an integrated circuit or die.In some embodiments, multiple discrete operational circuitry componentsare provided.

In some embodiments, the multiple electrical contacts 408 include atleast four electrical contacts 408(1), 408(2), 408(3), and 408(4). Inother embodiments, the device may include as many electrical contacts asis required. Some embodiments include an array of multiple rows 428 and430 of electrical contacts 408, as shown in FIG. 4C. The electricalcontacts may take on any form such as metallic bumps or pads formed oretched onto the surface of the device 402. In some embodiments,electrical contacts 408(1) and 408(2) are separated from one another bya predetermined pitch (q). Similarly, electrical contacts 408(3) and408(4) are separated from one another by a predetermined pitch (q). Alsoin some embodiments, each electrical contact on the second surface 420of the device is aligned with a respective electrical contact on thefirst surface 418 of the device. For example, electrical contact 408(3)is aligned or collinear with electrical contact 408(1) along animaginary line that is perpendicular to the first and second surfaces;electrical contact 408(4) is aligned (e.g., collinear) with electricalcontact 408(2) along an imaginary line that is perpendicular to thefirst and second surfaces; electrical contact 408(1) is separated fromelectrical contact 408(2) by a pitch q; and contact 408(3) is separatedfrom electrical contact 408(4) by the pitch q.

In some embodiments of the invention, the first electrical contact408(1) is electrically coupled to the operational circuitry 406 via anoperational circuitry electrical conductor 410. The second electricalcontact 408(2) is electrically coupled to the third electrical contact408(3), which is mechanically coupled to the second surface 420 of thedevice 402, via a first electrical conductor 412. The second electricalcontact 408(2) is also electrically coupled to the fourth electricalcontact 408(4), which is mechanically coupled to the second surface 420of the device 402, via a second electrical conductor 414. The electricalconductors may be any suitable electrical conductors, such as wires,redistribution layers, vias, or the like. In other embodiments of theinvention, additional electrical contacts may be electrically coupled toone another via additional electrical conductors that are similar tothose described above.

As shown in FIG. 4A, when the two devices 402(1) and 402(2) are arrangedin a stack, an electrical connection is either formed between the thirdelectrical contact 408(3) of the first device 402(1) and the firstelectrical contact 408(1) of the second device 402(2), or between thefourth electrical contact 408(4) of the first device 402(1) and thesecond electrical contact 408(2) of the second device 402(2). Thiselectrical connection may be formed by a solder bead 416 or the like. Asshown in FIG. 4A, an electrical connection is formed between the thirdelectrical contact 408(3) of the first device 402(1) and the firstelectrical contact 408(1) of the second device 402(2). Accordingly, inuse, a signal to be routed to the operational circuitry 406 of the firstdevice 402(1) is communicated to the first electrical contact 408(1) ofthe first device 402(1); and communicated from the first electricalcontact 408(1) to the operational circuitry 406 of the device 402(1) viathe operational circuitry conductor 410 of the first device 402(2).However, to route a signal to the operational circuitry 406 of thesecond device 402(2) in the stack, the signal is communicated to theelectrical contact 408(2) of the first device 402(1); communicatedthrough the first conductor 412 to the third electrical contact of thefirst device 402(1); communicated from the third electrical contact ofthe first device 402(1) to the first electrical contact 408(1) of thesecond device 402(2); and communicated from the first electrical contact408(1) of the second device 402(2) to the operational circuitry 406 ofthe second device 402(2) via the operational circuitry conductor 410 ofthe second device 402(2).

Similarly, FIG. 4B shows a schematic cross-sectional side view of thepoint-to-point interconnection system of FIGS. 4A and 4C, as viewedalong line 4B-4B′ of FIG. 4C. Here an electrical connection is madebetween the fourth electrical contact of the first device 402(1) and thesecond electrical contact of the second device 402(2); and between thethird electrical contact of the second device 402(2) and the firstelectrical contact 408(1) of the third device 402(3). A signal routed tothe first electrical contact of the first device 402(1) is routed to theoperational circuitry 406 of the first device, while a signal routed tothe second electrical contact of the first device 402(1) is routed tothe operational circuitry of the third device 402(3). Accordingly, byplacing electrical connections between predetermined electricalcontacts, signals can be communicated through the device alongconductors 412, 414 or routed to the operational circuitry of thedevice. Accordingly, the identical (or substantially similar) layout ofelectrical contacts and interconnecting conductors on the devices allowspoint-to-point connections to be made to all of the devices in the stackwithout requiring a customized RDL for one or more of the devices.

The above described systems allow signals to be passed through the stackfrom one device to the next. In some embodiments, each signal is alsoshifted one position laterally (in a direction perpendicular to theprimary vertical direction of the stack). This permits a signal to befed into the vertical stack at the bottom device, and be received at adevice higher in the stack. This is facilitated by designing theidentical pattern of electrical contacts (or RDLs) for all devices inthe stack. The above mentioned embodiments permit a uniquepoint-to-point signal (like a chip select for a memory die) to be drivento each device.

While the foregoing description and drawings represent the preferredembodiments of the present invention, it will be understood that variousadditions, modifications and substitutions may be made therein withoutdeparting from the spirit and scope of the present invention as definedin the accompanying claims. In particular, it will be clear to thoseskilled in the art that the present invention may be embodied in otherspecific forms, structures, arrangements, proportions, and with otherelements, materials, and components, without departing from the spiritor essential characteristics thereof. The presently disclosedembodiments are therefore to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims, and not limited to the foregoingdescription.

1. A point-to-point interconnection system for stacked devices,comprising: a device comprising: a substrate having opposing first andsecond surfaces; operational circuitry; a first electrical contactmechanically coupled to the first surface of the substrate andelectrically coupled to the operational circuitry; a second electricalcontact mechanically coupled to the first surface; a third electricalcontact mechanically coupled to the second surface opposite the firstelectrical contact; a conductor electrically coupling the secondelectrical contact to the third electrical contact.
 2. Thepoint-to-point interconnection system of claim 1, wherein the devicefurther comprises: a fourth electrical contact mechanically coupled tothe first surface; a fifth electrical contact mechanically coupled tothe second surface opposite the second electrical contact; an additionalconductor that electrically couples the fourth electrical contact to thefifth electrical contact.
 3. The point-to-point interconnection systemof claim 2, wherein the first electrical contact and the secondelectrical contact are separated from one another by a predefineddistance, and the second electrical contact and the fourth electricalcontact are separated from one another by the predefined distance. 4.The point-to-point interconnection system of claim 3, wherein the thirdand fifth connectors are separated from one another by the predefineddistance.
 5. The point-to-point interconnection system of claim 4,further comprising an additional device substantially identical to thedevice, where the additional device is stacked adjacent the device withthe first surface of the additional device located adjacent the secondsurface of the device, and where the first electrical contact of theadditional device is aligned with and is electrically coupled to thethird electrical contact of the device, and the third electrical contactof the additional device is aligned with and is electrically coupled tothe fifth electrical contact of the device.
 6. The point-to-pointinterconnection system of claim 5, further comprising one other devicesubstantially identical to the device and the additional device, wherethe other device is stacked adjacent the additional device with thefirst surface of the other device located adjacent the second surface ofthe additional device, and where the first electrical contact of theother device is aligned with and is electrically coupled to the thirdelectrical contact of the additional device.
 7. The point-to-pointinterconnection system of claim 1, further comprising an additionaldevice substantially identical to the device, where the additionaldevice is stacked adjacent the device with the first surface of theadditional device located adjacent the second surface of the device, andwhere the first electrical contact of the additional device is alignedwith and is electrically coupled to the third electrical contact of thedevice.
 8. The point-to-point interconnection system of claim 1, furthercomprising an additional device having first, second, and thirdelectrical contacts located at substantially identical positions topositions of the to the first, second, and third electrical contacts onthe device, where the additional device is stacked adjacent the devicewith the first surface of the additional device located adjacent thesecond surface of the device, and where the first electrical contact ofthe additional device is aligned with and is electrically coupled to thethird electrical contact of the device.
 9. The point-to-pointinterconnection system of claim 1, wherein the device is an integratedcircuit die.
 10. The point-to-point interconnection system of claim 1,wherein the device is an integrated circuit package containing at leastone die.
 11. The point-to-point interconnection system of claim 1,wherein the device is an memory module containing at least one die. 12.The point-to-point interconnection system of claim 1, wherein the deviceis an integrated circuit package containing multiple integrated circuitdie, where the operational circuitry is disposed within one of themultiple die.
 13. The point-to-point interconnection system of claim 1,wherein the first and third electrical contacts are aligned with oneanother along an imaginary line that is substantially perpendicular tothe first and second sides of the device.
 14. The point-to-pointinterconnection system of claim 1, wherein the operational device isembedded into the substrate.
 15. The point-to-point interconnectionsystem of claim 1, wherein the operational device is mounted on thesubstrate.
 16. The point-to-point interconnection system of claim 1,wherein the conductor is formed from: a first redistribution layer atthe first surface; a second redistribution layer at the second surface;and a third redistribution layer coupling the first layer to the secondlayer at an edge of the device that is substantially perpendicular tothe first layer and the second layer.
 17. The point-to-pointinterconnection system of claim 1, wherein the conductor comprises aredistribution layer that wraps around an edge of the device.
 18. Thepoint-to-point interconnection system of claim 1, wherein the conductoris offset from the second electrical contact at the second surface bythe same distance as between the first electrical contact and the secondelectrical contact.
 19. The point-to-point interconnection system ofclaim 1, wherein the first and second electrical contacts form part of afirst array of electrical contacts on the first surface, and the thirdelectrical contact forms part of a second array of electrical contactson the second surface.
 20. The point-to-point interconnection system ofclaim 1, further comprising: a fourth electrical contact on the secondsurface opposite the second electrical contact; and an additionalconductor coupling the second electrical contact to the fourthelectrical contact.
 21. The point-to-point interconnection system ofclaim 20, further comprising an additional device substantiallyidentical to the device, where the additional device is stacked adjacentthe device with the first surface of the additional device locatedadjacent the second surface of the device, and where the firstelectrical contact of the additional device is aligned with the thirdelectrical contact of the device, and the second electrical contact ofthe additional device is aligned with the fourth electrical contact ofthe device, and wherein either the third electrical contact of thedevice is electrically coupled to the first electrical contact of theadditional device, or the fourth electrical contact of the device iselectrically coupled to the second electrical contact of the additionaldevice.
 22. A point-to-point interconnection system for stacked devices,comprising: a device having opposing first and second surfaces, thedevice comprising; operational circuitry; a first electrical contactmechanically coupled to the first surface of the device and electricallycoupled to the operational circuitry; a second electrical contactmechanically coupled to the first surface; a third electrical contactmechanically coupled to the second surface opposite the first electricalcontact; a conductor electrically coupling the second electrical contactto the third electrical contact.
 23. The point-to-point interconnectionsystem of claim 22, wherein the device further comprises: a fourthelectrical contact mechanically coupled to the first surface; a fifthelectrical contact mechanically coupled to the second surface oppositethe second electrical contact; an additional conductor that electricallycouples the fourth electrical contact to the fifth electrical contact.24. The point-to-point interconnection system of claim 23, wherein thefirst electrical contact and the second electrical contact are separatedfrom one another by a predefined distance, and the second electricalcontact and the fourth electrical contact are separated from one anotherby the predefined distance.
 25. The point-to-point interconnectionsystem of claim 24, wherein the third and fifth connectors are separatedfrom one another by the predefined distance.
 26. The point-to-pointinterconnection system of claim 22, further comprising an additionaldevice substantially identical to the device, where the additionaldevice is stacked adjacent the device with the first surface of theadditional device located adjacent the second surface of the device, andwhere the first electrical contact of the additional device is alignedwith and is electrically coupled to the third electrical contact of thedevice.
 27. The point-to-point interconnection system of claim 22,wherein the device is an integrated circuit die.
 28. The point-to-pointinterconnection system of claim 22, wherein the device is an integratedcircuit package containing at least one die.
 29. The point-to-pointinterconnection system of claim 22, wherein the operational device isembedded into the substrate.
 30. The point-to-point interconnectionsystem of claim 22, wherein the operational device is mounted on thesubstrate.
 31. A stacked device assembly comprising: a first device anda substantially identical second device stacked on top of the firstdevice, where each device has a first surface and an opposing secondsurface, and each device comprises: a substrate having opposing firstand second surfaces; operational circuitry; a first electrical contactmechanically coupled to the first surface of the device and electricallycoupled to the operational circuitry; a second electrical contactmechanically coupled to the first surface; a third electrical contactmechanically coupled to the second surface opposite the first electricalcontact; a conductor electrically coupling the second electrical contactto the third electrical contact, wherein the second device is stackedadjacent the first device with the first surface of the second devicelocated adjacent the first surface of the first device, and where thefirst electrical contact of the second device is aligned with and iselectrically coupled to the third electrical contact of the device. 32.The stacked device assembly of claim 31, wherein each device furthercomprises: a fourth electrical contact mechanically coupled to the firstsurface; a fifth electrical contact mechanically coupled to the secondsurface opposite the second electrical contact; an additional conductorthat electrically couples the fourth electrical contact to the fifthelectrical contact.
 33. The stacked device assembly of claim 32, whereinthe first electrical contact and the second electrical contact of eachdevice are separated from one another by a predefined distance, and thesecond electrical contact and the fourth electrical contact of eachdevice are separated from one another by the predefined distance. 34.The stacked device assembly of claim 31, wherein the devices areintegrated circuit dies.
 35. The stacked device assembly of claim 31,wherein the devices are an integrated circuit packages each containingat least one die.
 36. The stacked device assembly of claim 31, whereinthe operational devices are embedded into the substrate of each device.37. The stacked device assembly of claim 31, wherein the operationaldevices are mounted on the substrate of each device.